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Contact Information:

photo of William Halvorson
Name:
Halvorson, William (Bill)
Title:
Research Ecologist
Discipline(s):
Plant Ecology, Ecosystem Ecology, Ecosystem Management, Natural Resource Management
Research Station:
SDRS
Work Address:
125 Biological Sciences East, University of Arizona, Tucson, AZ 85721
Telephone Number:
(520)621-1174 fax:(520)670-5001
Email Address:
bill_halvorson@usgs.gov

Biographical Sketch:

Dr. Bill Halvorson has been working on research and management of arid lands since 1962, when he was an undergraduate at Arizona State University and worked as a horticultural technician for the Desert Botanical Garden. Bill obtained a B.S. from ASU in 1965 and an M.S. from the University of Illinois in 1967. The research for his thesis was done on the Kaibab Plateau while working for Grand Canyon National Park. After graduating with a Ph.D. from ASU in 1970, Dr. Halvorson spent eight years at the University of Rhode Island before moving on to work for the federal government in 1979. Throughout his career, Bill has always had, "one foot in academics and one foot in land management."

Today, Dr. Halvorson is a research ecologist with the USGS Southwest Biological Science Center's Sonoran Desert Research Station, a cooperative research unit within the University of Arizona's School of Natural Resources. His main research interests are in those aspects of landscape management and information management that assist land agencies, such as the National Park Service, U.S. Fish and Wildlife Service, Bureau of Land Management, and the USDA Forest Service, get the research answers they need. He is currently working with the National Park Service to develop comprehensive inventories of natural resources and nation-wide, long-term monitoring programs. Bill is also working with individuals from many agencies on the development of an interagency monitoring program for the Sonoran Desert, complete with a data and information management system that will allow sharing among a large groups of government and non-government agencies and groups. Dr. Halvorson's other specific interests include rare and alien plant ecology and management, fire ecology, and ecosystem management as it relates to natural resources, culture, and society.

  • Expertise
    • Endangered plant species ecology
    • Vegetation science
    • Ecosystem monitoring
    • Landscape Ecology
    • Ecosystem management
  • Education
    • Ph.D. 1970, Botany, Arizona State University. Tempe, AZ
    • M.S. 1967, Botany, University of Illinois, Urbana, IL
    • B.S. 1965, Botany, Arizona State University, Tempe, AZ
  • Membership in Professional Societies
    • Arizona/Nevada Academy of Science
    • California Botanical Society
    • Ecological Society of America
    • Sigma Xi
    • Society for Ecological Restoration
    • Southwestern Association of Naturalists

Project List

  • (Not yet specified)

Publications, Maps, and other Products

  1. Powell, B., E. Albrecht, W. Halvorson, C. Schmidt, K. Docherty, P. Anning. 2006. Vascular Plant and Vertebrate Inventory of Gila Cliff Dwellings National Monument. U.S. Department of the Interior, USGS and National Park Service, Open-File Report 2005-1187. [Open-File Report]
  2. Powell, B., E. Albrecht, C. Schmidt, W. Halvorson, P. Anning, and K. Docherty. 2006. Vascular Plant and Vertebrate Inventory of Casa Grande Ruins National Monument. U.S. Department of the Interior, USGS and Natoinal Park Service, Open-File Report 2005-1185. [Open-File Report]
  3. Schmidt, C. A., C. A. Drost, and W. L.Halvorson. 2006. Vascular Plant and Vertebrate Inventory of Montezuma Castle National Monument. USGS Open File Report 2005-1163. [Open-File Report]
  4. Powell, B., C. Schmidt, and W. Halvorson. 2006. Vascular plant and vertebrate inventory of Fort Bowie National Historic site. USGS. Open File Report 2005-1167, December 2006. [Open-File Report]
  5. Powell, B., W. Halvorson, C. Schmidt. 2006. Vascular plant and vertebrate inventory of Saguaro National Park, Rincon District. USGS Open File Report 2006-1075. [Open-File Report]
  6. Powell, B.F., E.W. Albrecht, W.L. Halvorson, C.A. Schmidt, P. Anning, and K.Docherty. 2005. Vascular plant and vertebrate inventory of Tumacacori National Historic Park. USGS Open File Report 2005-1142. [Open-File Report]
  7. Powell, B.F., E.W. Albrecht, W. L. Halvorson, C.A. Schmidt, P. Anning, and K. Docherty. 2005. Vascular plant and vertebrate inventory of Tuzigoot National monument. USGS Open File Report 2005-1347. [Open-File Report]
  8. Gebow B.S, E.W. Albrecht, D. Caldwell, B.F. Powell, J.A. Hubbard, W.L. Halvorson. 2004. Sonoran Desert Network Inventory and Monitoring Program: Assessing the State of Ecological Resources in 11 Southwestern National Parks. National Park Service, Sonoran Desert Network. Tucson, AZ. 10 p. [Technical Report]
  9. Halvorson W. L. 2004. Ecosystem Restoration on the California Channel Islands. International Journal of Ecology and Environmental Sciences, National Institute of Ecology, India, 30(3): 163-168. [Journal Article]
  10. Halvorson W. L. 2004. Challenges of Managing Information. Biodiversity and Management of the Madrean Archipelago II, Connecting Mountain Islands and Desert Seas and the 5th Conference on Research and Resource Management in Southwestern Deserts. Tucson, AZ, May 2004. (Invited). [Proceedings]
  11. Albrecht E., B. Powell, D. Swann, W.L. Halvorson. 2004. Species richness as an avian community monitoring parameter. Oral Presentation. Biodiversity and Management of the Madrean Archipelago II, Connecting Mountain Islands and Desert Seas and the 5th Conference on Research and Resource Management in Southwestern Deserts. Tucson, AZ, May 2004. [Proceedings]
  12. Powell B., E. Albrecht, R. Steidl, W. L. Halvorson. 2004. Monitoring Vertebrates in the Sonoran Desert: Choosing the best parameter(s) among hundreds of choices. Oral Presentation. Biodiversity and Management of the Madrean Archipelago II, Connecting Mountain Islands and Desert Seas and the 5th Conference on Research and Resource Management in Southwestern Deserts. Tucson, AZ, May 2004. [Presentation]
  13. Schmidt C., B. Powell, E. Albrecht, W. L. Halvorson. 2004. Successful Biological Inventories in Sonoran Desert National Parks. Poster Presentation. Biodiversity and Management of the Madrean Archipelago II, Connecting Mountain Islands and Desert Seas and the 5th Conference on Research and Resource Management in Southwestern Deserts. Tucson, AZ, May 2004. [Proceedings]
  14. Halvorson W. L. 2004. Historical Perspectives on the Concept of Ecosystem Degradation. Journal of Ecology and Environmental Sciences, National Institute of Ecology, India, (in press). Journal of Ecology and Environmental Sciences, National Institute of Ecology, India 30(3): 163-168. [Journal Article]
  15. Castellanos A. E., M. A. Martinez, J. Llano, W. L. Halvorson, M. Espiricueta, I. Espejel. 2004. Successional trends in Sonoran Desert abandonded agricultural fields. Journal of Arid Environments 60(3): 437-455. [Journal Article]
  16. Halvorson W. L. 2004. Challenges of Managing Information. Biodiversity and Management of the Madrean Archipelago II, Connecting Mountain Islands and Desert Seas and the 5th Conference on Research and Resource Management in Southwestern Deserts, Proceedings. U.S. Forest Servic, pp 182-184. [Book Chapter]
  17. Hobbs R. J., M. A. Davis, L. B. Slobodkin, R. T. Lackey, W. L. Halvorson, W. Throop. 2004. Restoration ecology: the challenge of social values and expectations. Frontiers in Ecology and the Environment 2(1): 43-48. [Journal Article]
  18. Morales S. M., W. L. Halvorson. 2004. Use of transplanted saguaros by native cavity nesting birds. Desert Plants 20(1):43-48. [Journal Article]
  19. Powell B.F., E.W. Albrecht, W.L. Halvorson, K. Docherty. 2003. Biological inventory report for the Sonoran Desert Network: 2002. Annual Report No. 2. Sonoran Desert Network Inventory Program. USGS Sonoran Desert Field Station and School of Renewable Natural Resources, University of Arizona, Tucson. 53 p. [Technical Report]
  20. Malusa J., W. L. Halvorson, D. Angell. 2003. Distribution of the Exotic Mustard, Brassica tournefortii, in the Mohawk Dunes and Mountains, Arizona. Desert Plants 19:31-36. [Journal Article]
  21. Halvorson W. L. 2003. Restoration of the California Channel Islands. International Conference on EcoRestoration, Dehradun, India, October 2003. (Invited). [Proceedings]
  22. Halvorson W. L. 2003. Historical Perspectives on Concept of Degradation. International Conference on EcoRestoration, Dehradun, India, October 2003. (Invited Keynote Address). [Proceedings]
  23. Halvorson W. L. 2003. The scope and need for restoration ecology. Ecological Society of India, Pune, India (Invited). [Proceedings]
  24. Halvorson W. L., P. Guertin. 2003. Status of introduced plants in southern Arizona parks. Final Report, USGS Weeds in the West Program and National Park Service, Cooperative Agreement. [Technical Report]
  25. Halvorson W. L., A. E. Castellanos, J. Murrieta-Salidar. 2003. Sustainable land use requires attention to ecological signals. Environmental Management 32(5): 551-558. [Journal Article]
  26. Briggs M., D. Lett, C. Gorman, R. Gimblett, W. Halvorson. 2002. Monitoring Riparian Ecosystems. Final Report, Arizona Game and Fish Dept. Heritage Grant. [Technical Report]
  27. DiBari J.N., W. L. Halvorson, R. Steidl. 2002. Linking patch dynamics, landscape organization, patch-size scaling, and landscape connectivity. Final Report, U. S. Geological Survey, Cooperative Agreement. . [Technical Report]
  28. Hobbs R. J., W. L. Halvorson, S. DeStefano. 2002. Habitat relationships and productivity of birds of prey in the Altar Valley, Arizona. Final Report, Arizona Game and Fish Dept. Heritage Grant. [Technical Report]
  29. Malusa J, W. Halvorson, D. Angell. 2002. Distribution of the exotic mustard Brassica tournefortii in the Mohawk Dunes and Mountains, Arizona. Fourth conference on Research and Resource Management in Southwestern Deserts, Tucson, AZ May 2002. [Proceedings]
  30. Castellanos A. E., M. J. Martinez, J. Murrieta, W. Halvorson, R. Castillo, I. Espejel. 2002. Abandonment history and successional trends in Sonoran Desert agricultural old fields. Joint Annual Meetings of the Ecological Society of America and Society for Ecological Restoration, Tucson, AZ, August 2002. [Proceedings]
  31. Hobbs R. J., S. DeStefano, W. L. Halvorson. 2002. Nest success, productivity, and nest site selection of red-tailed hawks in a southern Arizona semi-desert grassland. National Wildlife Society Meeting. [Proceedings]
  32. Hobbs R. J., S. DeStefano, W. L. Halvorson. 2002. Nest success, productivity, and nest site selection of red-tailed hawks in a southern Arizona semi-desert grassland. Joint Annual Meetings of the Ecological Society of America and Society for Ecological Restoration, Tucson, AZ, August 2002. [Proceedings]
  33. Malusa J., W. L. Halvorson, D. Angell. 2002. Distribution of Sahara Mustard in the Mohawk Dunes and Mountains, Arizona. P. 79 in Halvorson, W. L. and B. S. Gebow. 2002. Meeting Resource Management Information Needs: Fourth Conference on Research and Resource Management in the Southwestern Deserts. Extended Abstracts. USGS Sonoran Desert Field Station, The University of Arizona, Tucson 154 p. [Proceedings]
  34. Halvorson W.L., K. Thomas, L. Graham, M. Kunzmann, P. Bennett, C. Van Riper . 2001. Arizona GAP Report. C. Drost with B. S. Gebow, editor Final Report to the National GAP Office, USFWS, NBS, and USGS Gap Analysis Program. [Technical Report]
  35. Malusa J., W. L. Halvorson, D. Angell. 2001. Distribution of the exotic mustard, Brassica tournefortii Gouan, in the Mohawk Dunes and Mountains, March 2001. Final Report, Yuma Office of Bureau of Land Management, Cooperative Agreement. [Technical Report]
  36. Halvorson W. L., B. S. Gebow. 2000. Saguaro National Park floristic surveys. Technical Report No. 68. U.S. Geological Survey, Sonoran Desert Field Station, The University of Arizona, Tucson. [Technical Report]
  37. Halvorson W. L., B. S. Gebow. 2000. Meeting Resource Management Information Needs: Fourth Conference on Research and Resource Management in the Southwestern Deserts, Extended Abstracts. USGS Sonoran Desert Research Station, The University of Arizona, Tucson. [Book]
  38. Halvorson W. L., B. S. Gebow. 2000. Creative Cooperation in Resource Management: Third Conference on Research and Resource Management in the Southwestern Deserts. Extended Abstracts. USGS Sonoran Desert Field Station, The University of Arizona, Tucson. [Book]
  39. Schwalbe C. R., T. C. Esque, W. L. Halvorson, D. F. Haines. 2000. Annual Grass Invasions and Fire in the Mojave and Sonoran Deserts. USGS National Program Review on Invasives. Annapolis, MD. 23-25 October. [Proceedings]
  40. Schwalbe C. R., T. C. Esque, P. J. Anning, W. L. Halvorson. 2000. Exotic grasses, long-lived species and managing desert landscapes: a case history at Saguaro National Park. Extended abstract and presentation. Page 87 in Halvorson and Gebow 2000. [Presentation with Abstract]
  41. Schwalbe C. R., T. C. Esque, P. J. Anning, W. L. Halvorson. 2000. Exotic grasses, long-lived species, and managing desert landscapes: a case history at Saguaro National Park. Third Conference on Research and Resources Management in the Southwestern Deserts, Tucson, AZ, May 2000. [Proceedings]
  42. Halvorson W. L. 2000. Historical perspectives on the concept of ecosystem degradation. Annual Meeting of the Society for Ecological Restoation, Liverpool, United Kingdom. (Presented). [Presentation]
  43. Halvorson W. L., P. P. Guertin. 2000. Invaders in the Desert. Third Conference on Research and Resources Management in the Southwestern Deserts, Tucson, AZ, May 2000. [Proceedings]
  44. Cornelius S. E., G. Acheson, W. L. Halvorson, B. Miller, V. Morrill, M. Taylor, D. Tiller, B. Wellman. 2000. Building a case for ecosystem monitoring in the Sonoran Desert. Third Conference on Research and Resources Management in the Southwestern Deserts, Tucson, AZ, May 2000. [Proceedings]
  45. Halvorson, W. L., M.R. Kunzmann. 2000. Recent advances in information management. Presentation to the USGS Reston Informatics and I&M staff. (Invited). [Proceedings]
  46. Schwalbe C. R., T. C. Esque, P. J. Anning, W. L. Halvorson. 2000. Exotic grasses, long-lived species, and managing desert landscapes: a case history at Saguaro National Park. P. 87 in W.L. Halvorson and B.S. Gebow (eds), Creative Cooperation in Resource Management, Proceedings of the Third Conference on Research and Resources Management in the Southwestern Deserts, USGS Sonoran Desert Field Station, University of Arizona, Tucson, AZ. [Proceedings]
  47. Halvorson W. L., P. P. Guertin. 2000. Invaders in the Desert. Pp. 42-43 in W.L. Halvorson and B.S. Gebow (eds), Creative Cooperation in Resource Management, Proceedings of the Third Conference on Research and Resources Management in the Southwestern Deserts, USGS Sonoran Desert Field Station, University of Arizona, Tucson, AZ. [Proceedings]
  48. Cornelius S. E., G. Acheson, W. L. Halvorson, B. Miller, V. Morrill, M. Taylor, D. Tiller, B. Wellman. 2000. Building a case for ecosystem monitoring in the Sonoran Desert. Pp. 21-22 in W.L. Halvorson and B.S. Gebow (eds), Creative Cooperation in Resource Management, Proceedings of the Third Conference on Research and Resources Management in the Southwestern Deserts, USGS Sonoran Desert Field Station, University of Arizona, Tucson, AZ. [Proceedings]
  49. Davis K., W. L. Halvorson. 2000. A study plan to inventory vascular plants and vertebrates: Sonoran Desert Network, National Park Service. Final Report, National Park. Service, Cooperative Agreement. [Technical Report]
  50. Halvorson W. L. 2000. Arizona vegetation map. Final Report to the Arizona Dept. of Game and Fish, USFWS, NBS, USGS GAP Program. [Technical Report]
  51. Halvorson W.L., B. S. Gebow. 2000. Creative Cooperation in Resource Management. Proceedings of the Third Conference on Research and Resource Management in the Southwestern Deserts. USGS Sonoran Desert Field Station, University of Arizona. 109 p. [Proceedings]
  52. Falk D. A., M. K. Briggs, W. L. Halvorson. 1999. The riparian ranking (R3) System: A tool for setting Priorities in a Resource-Limited World. Pp 24-27 in P. B. Shafroth, B. Tellman, and M.K. Briggs (tech. cords.). Riparian Ecosystem Restoration in the Gila River Basin: Opportunities and Constraints, Workshop Proceedings. Water Resources Research Center, The University of Arizona, Tucson, AZ. [Book Chapter]
  53. Halvorson W.L. 1999. Research and Ecosystem Monitoring in the Sonoran Desert. USFWS Desert Ecology and and Refuge Management Workshop, Tucson, October 1999 (Invited). [Proceedings]
  54. Swantek P. J., W. L. Halvorson, C. R. Schwalbe. 1999. Analysis of fire history in Saguaro National Park using Geographic Information Systems. Extended abstract and presentation. Pages 121-124 in Benson and Gebow 1999. [Presentation with Abstract]
  55. Halvorson W.L. 1999. A Review of Science and Ecosystem Management in the National Parks. Annual National Meeting of the National Park Service Resource Managers and the Annual Conference of the Society for Ecological Restoration, San Francisco, CA, September 23-25, 1999 (Invited). [Proceedings]
  56. Hiett K. L., W. L. Halvorson. 1999. Inventory and Assessment of Avifauna and a Monitoring Protocol Proposal for Tonto National Monument, Arizona. Cooperative Park Studies Unit, University of Arizona, Tucson, AZ. Technical Report No. 62. [Technical Report]
  57. Falk D. A., M. K. Briggs, W. L. Halvorson. 1999. The riparian ranking (R3) System: A tool for setting Priorities in a Resource-Limited World. Restoration Conference, March 1999, Tucson, AZ (Invited). [Proceedings]
  58. Halvorson W. L. 1999. A Review of Science and Ecosystem Management in the National Parks. George Wright Society Meeting, Asheville, NC March 23-25, 1999 (Invited). [Presentation]
  59. Halvorson W. L. 1999. Historical perspectives on the concept of ecosystem degradation (Invited). Meeting of the American Society for Environmental History, Tucson, AZ, April 16-17, 1999. [Proceedings]
  60. Swantek P. J., W. L. Halvorson, C. R. Schwalbe. 1999. GIS Database Development to Analyze fire history in southern Arizona and beyond, an example from Saguaro National Park. Cooperative Park Studies Unit, University of Arizona, Tucson, AZ. Technical Report No. 61. [Technical Report]
  61. Halvorson W. L., C. Eastin. 1999. The partnership between park wild life management policy and landscape wild life management policy. How shall we then manage. George Wright Society Bulletin 16: 77-90. [Journal Article]